As means for conveying a truck having no driving source on a certain fixed path, known is, as disclosed in the Japanese Utility Model Publication No. Sho 59-2865, an apparatus provided with a catcher downwardly suspended from the underside of the truck, a chain extended along a certain path, and projections prepared as a pusher, disposed at a plurality of points along the lengthwise direction of the chain, and adapted to be engageable with said catcher. According to this apparatus, conveying force of the chain is transmitted from the projection as the pusher to the catcher and conveys the truck on a fixed path.
For conveying a trolley having no driving source on a fixed path, as disclosed in the Japanese Utility Model Laid-Open No. Sho 59-131357, known is an apparatus provided with a follower dog which is to be moved upward and is disposed on the trolley supported and guided by the trolley guide rail, a chain supported and guided by the rail for the trolley driving device arranged above the trolley guide rail, and driving projection on the chain with which said follower dog is engageable. In this apparatus, driving force of the chain is transmitted through the driving projections to the follower dog for conveying the trolley on a certain path.
These known apparatuses, however, require an arrangement of the chain throughout the length of a path and the entire length of the path is structurally complicated, whereby the catcher and the follower dog must be fixed to the truck and trolley with high precision.